I am a 45 year old woman with a bladder infection. I let it go for over a week, before going to the doctor. I tried to make it go away on it's own. I finally couldn't stand it anymore. I went and had a urine test it was positive. They sent it off for culture. The doctor prescribed bactrim that day. Five days later, today I got a call from the doctor. They said my infection is resistant to bactrim. They gave me Cipro. Is it normal for me to feel very tired? What kind of bacteria is resistant to bactrim?